This technology relates to a method and system of producing iron electrolytically using iron oxide as a starting material.
Iron is currently produced commercially in blast furnaces where iron ore is reduced by coke to cast iron. This millennia old, greenhouse gas emitting, carbothermal process is responsible for 25% of all carbon dioxide global released by industry. In order to reduce carbon dioxide emissions it is desirable to develop alternate processes to produce iron with a substantial reduction or elimination of carbon dioxide production.
Previous attempts to produce iron from naturally occurring materials by electrowinning have faced challenges and have not provided a pathway to the commercial, carbon dioxide-free production of iron. Attempts have included room temperature electrowinning, challenged by too high a voltage to be efficient, and molten iron oxides, which faced the material's challenges of very high temperature (hematite melts at 1565° C.). Non-naturally occurring iron materials have been used as a reactant. Non-naturally occurring starting materials represent additional costs—both environmentally and economically.
There remains a need in the art for a method of electrowinning iron from naturally occurring materials, at low voltage, at a temperature below that of the melting point of iron oxides, at high rate, and without carbothermal carbon dioxide emission.